Door check



F. L. THARP DOOR CHECK Feb. 23, 1943.

Filed May 5, 1941 I '7 v n 1: I NVENTOR fled 4. 7 %drfi a w S A TTORNE Y5.

Patented Feb. 23, 1943 UNITED STATES PATENT OFFICE DOOR .GHECK Fred L. Tharp, East Detroit, Mich.

Application May 5, 1941, Serial No. 391,819

8' Claims.

This invention relates to building hardware and more particularly to an improved device for cushioning and checking an outside door of a building and preventing it from crashing against the wall when the door is caught by a strong wind. I

One of the objects-cf the present invention is to provide an improved door check which offers two stages of cushioning resiliency to the opening movements of the door.

Another object of the invention is to provide an. improved door check which offers light and substantially uniform yielding resistance to normal opening movements of the door, and relatively stiff gradually increasing yielding resistance to opening of the door beyond a predetermined position.

A further object of the invention is to provide an improved door check of the foregoing character which includes only one spring, which spring is so arranged that it is not overstretched or overdeflected above its elastic limit and therefore cannot take an objectionable permanent set either longitudinally or transversely.

A still further object of the invention is to provide an improved door check which includes a single relatively short coil spring of considerable resistance and operative for resisting excessive opening movements of the door but not the normal operation thereof.

It is an added object of the present invention to provide an improved device of the foregoing character which is simple in construction, includes only a small number of parts, is safe and dependable in operation and also relatively inexpensive to manufacture.

Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawing forming a part of this specification wherein like reference characters designat corresponding parts in the several views.

Fig. 1 is a fragmentary view in elevation of a door and door frame construction including a door check embodying the present invention.

Fig. 2 is a horizontal section taken substantially through lines 2-2 of Fig. 1 looking in the direction of the arrows.

Fig. 3 is an enlarged fragmentary view of the portion of the door check embraced within the circle 3 of Fig. 1.

Fig. 4 is an enlarged fragmentary view of the portion of the door check embraced within the circle 4 of Fig. 2.

Referring to the drawing, wherein one embodiment of' the invention is illustrated. by way of example, there is shown at I0 a door frame to which is hinged at I 2 an inner door I I. Mounted in the door frame is an outside or storm door I3 which is hinged thereto at I4.

The present door check comprises a suitable bracket I5 which may be attached by screws I6 to the bottom face of the upper jamb rail or header of the door frame, as clearly illustrated in the drawing. The bracket I5 is provided with a straight channel portion I1 extending parallel to the plane of the door l3 when closed. This straight channel portion I1 merges into a flared channel portion Ho. The depth of the channel is preferably such as to fully confine a coil spring I8 which normally extends in a straight line direction into the rectilinear portion I I of the channel, the end l8a of the spring being hooked through an aperture in the bracket to anchor the spring in position. The coil spring I8 has an integral hooked extension [8b connected to a chain I9 of suitable length, the end of the chain being attached by means of a suitable bracket 20 to the inner face of the storm door I3 adjacent the upper edge thereof.

As can be clearly seen from an examination of the drawing, as the storm door I3 commences its opening movement, the chain [9 soon tightens up and begins exerting a force on the end of the spring l8 transversely thereof. Due to the exertion of this force the spring I8 is bent bodily in the bracket I5. This action is clearly seen in Fig. 4 wherein the spring in its dotted line position has been bent laterally so as to conform to the curvilinear shape of the flared channel portion IIa of the bracket. During this action no longitudinal stretching of the spring takes place, and such stretching does not occur until the door reaches a predetermined position determined by the length of the spring I8 and the chain I9.,

When this position of the door is reached the spring I8 and the chain I9 extend substantially along the same straight line, as illustrated in dotted lines in Fig. 2, and hence further opening of the door I3 operates to stretch the spring I8 longitudinally.

From the foregoing it will be seen that during normal use of the outer door I3 to permit ingress or egress, the spring I8 is bent transversely and does not present objectionably strong resistance to the opening of the door. On the other hand, should the door I3 be caught by a strong wind while in any open position and swung outwardly by thewind, the spring I8 will then resist,.with itslongitudinal'resiliency, the force of. the wind,

and since the spring is relatively stiff, considerable resisting force is thus presented to the action of the wind. The resistance of the spring progressively increases as the same is stretched longitudinally, and hence any danger of the door contacting the wall of the building is strongly resisted and any violent opening of the door by the force of a wind is cushioned.

It will thus be seen that one of the features of the present invention resides in the provision of a door check in which the main spring is not tensioned throughout the entire operative stroke of the door I3. On the contrary, any material or large deflection of the spring l8 occurs only after the door l3 has been swung to a-predetermined open position. The construction, however, is such that some spring action occurs even when the door is swung to the predetermined open position shown in Fig. 2, this occurring on.

account of the bending or distortion of the spring in a transverse direction. In other words, there is provided in accordance with the present invention a door check embodying preferably a single spring which passes through two stages of operation during the operative movement of the door: first, bodily bending of the spring substantially without any stretching of the spring for normal operation of the door, and second, longitudinal stretching of the spring for excessive opening of the door.

By virtue of the invention, therefore, I have eliminated the disadvantages of such previous devices as require the use of a relatively strong or stiff spring which ofiers objectionably strong resistance to the normal opening of the door and instead have provided an improved door check in which a single coil spring is used having two stages of resiliency.

I claim:

1. In a door check for a door hingedly mounted on a fixed structure, a single coil spring having one end connected to said door and another end anchored on said fixed structure, said spring being adapted to be bent bodily substantially without stretching as the door moves between its closed position and a predetermined open position, and to be progressively stretched as said door moves between said predetermined position and its fully open position.

2. In a door check for a door hingedly mounted on a fixed structure, an elongated member stretchable longitudinally and bendable transversely, said elongated member having one end anchored on said fixed structure and another end free thereof, and a substantially unstretchable member having one end anchored on said door and another end connected to the free end of said stretchable membenboth of said members being adapted to be disposed at an angle to each other as the door moves between its fully closed position and a predetermined intermediate position, and to be disposed along a straight line with respect to each other as said door moves between said intermediate position and its fully open position.

3. In a door check for a door hingedly mounted on a fixed structure and adapted to swing between its fully open and fully closed positions, two elongated members, at least one of said members being longitudinally stretchable, said members having connected ends, their opposite ends being anchored on said fixed structure and said door respectively, said members being further adapted to be disposed at an angle with respect to each other as the door moves between its fully closed position and a predetermined intermediate position, and to be disposed in alignment as said door moves between said intermediate position and its fully open position.

4. In a door check for a door hingedly mounted on a fixed structure and adapted to swing between its fully open and fully closed positions, two elongated members, at least one of said members being longitudinally stretchable and transversely bendable, said members having connected ends, their opposite ends being anchored on said fixed structure and said door respectively, said members being further adapted to be disposed at an angle with respect to each other with said bendable and stretchable member being bent as the door moves between its fully closed position and a predetermined intermediate position, and to be disposed in alignment with said bendable and stretchable member being stretched as said door moves between said intermediate position and its fully open position.

5. In a door check for a door hingedly mounted on a fixed structure and adapted to swing between its fully open and fully closed positions, two elongated members, at least one of said members being longitudinaly stretchable and transversely bendable, said members having connected ends, their opposite ends being anchored on said fixed structure and said door respectively, said members being further adapted to be disposed at an angle with respect to each other with said bendable and stretchable member being bent as the door moves between its fully closed position and a predetermined intermediate position, and to be disposed in alignment with said bendable and stretchable member being stretched as said door moves between said intermediate position and its fully open position, said bendable member being further adapted to be disposed substantially parallel to said door in the fully closed position thereof.

6. A door check for a door hingedly mounted on a fixed structure and adapted to swing thereon between its fully closed and fully open positions, said door check comprising a coil spring having an end secured to said fixed structure and a chain having one end attached to said door, the free ends of said spring and chain being connected together, said spring and chain being adapted to be disposed at an angle with respect to each other while the door is in positions between its fully closed position and a predetermined intermediate position of its operative stroke, andto be disposed along a straight line while the door is in positions between said intermediate position and its fully open position.

7. A door check for a door hingedly mounted on a fixed structure and adapted to swing thereon between its fully closed and fully open positions, said door check comprising a coil spring having an end secured to said fixed structure and a chain having one end attachedv to said door, the free ends of said spring and chain being connected together, said spring and chain being adapted to be disposed at an angle with respect to each other, said spring being bent transversely while the door is in positions between its fully closed position and a predetermined intermediate position of its operative stroke, and to be. disposed along a straight line with said spring being stretched longitudinally while the door is in positions between said intermediate position and its fully open position.

8. A door check for a door hingedly mounted on a fixed structure and adapted to swing thereon between its fully closed and fully open positions, said door check comprising a coil spring having an end secured on said fixed structure and a chain having one end attached to said door, the free ends of said spring and chain being connected together, said spring and chain being adapted to be disposed at an angle with respect to each other, said spring being bent transversely when the door is in a position between its fully closed position and a predetermined intermediate position of its operative stroke, and to be disposed along a straight line with said spring being stretched longitudinally when the door is in a position between said intermediate position and its fully open position, said spring being adapted to extend in the fully closed position of the door substantially parallel thereto.

FRED L. THARP. 

